I have never seen a grammar nazi offer criticism or "corrections" that weren't in some way classist, ableist, or racist (sometimes even misogynist!).
If you're unfamiliar, a grammar nazi is a person who will, unprompted, try to correct your language. Usually it's because you used different words or phrases than they expect, whether on purpose or by accident. They will stop conversations dead in their tracks to do this, because they care more about holding your language to some arbitrary standard than they care about communication and social rapport. To a grammar nazi, an unexpected word choice or mix-up of homophones is such a social faux-pas that it justifies the even bigger faux-pas of antagonizing one's conversational partner.
Language is one of those things that people love to use as an avenue of power and control. The intent of correcting someone's speech patterns is to shame what they see as an unwillingness to play by the same rules as them. Assimilatory politics like that is expressed towards anyone who falls outside the educated upper class,
All communication is to some extent assimilatory; there needs to be some sort of consensus within a given group about exactly what the words they use mean, otherwise they can't effectively and accurately communicate information between one another. It's very common to be resolving mismatches in semantics while having a conversation in order to maintain this consensus, and this isn't grammar nazism. What separates grammar nazism from superficially similar prosocial acts is the explicit refusal to engage with the content if it's delivered in what they deem to be the "wrong" pronunciation, syntax, choice of words, and sometimes even inflection. It's an inherently antisocial act that